Application of endovascular stents on the management of right ventricular to pulmonary artery conduit stenosis

JACC

|:ehnlaD r 199~

ABSIRA('r~

leaflets (46 vs, 20%, p = 0.C0"~) and moderate or severe mdral regurgitation (52 vs, 32%, p = 0,001 ) with :~utsignificant age or sex differences, Conclusions' TVP in ass¢ clarion with MVP is infrequent, even in a referral population, and presents in patients with more severe myxomatous valve disease~

(.Ir~d 57A

10:45 8~--~

Simu.l.tan_eoualy Implanted " C r l s o c r o u l n g " Slants PrOVlOe E x c e l l e n t Relief for P o s t o p e r a t i v e Bilateral

Proximal Pulmonary ArIew Stenosmu With Closely Related e a r l s

~-3~ ~

11:45 Enhen~KI Vls,,,sllutlon of Intrnvsscular Thrombus With t~lSU~!~-O?S Thrombus Targeting UltrHound Contrast Agsnt (MRX408): Evldenco From In Vivo E x l ~ r l m e n t a l E,'.hO¢lrdlographk: StudkHI

M, Takouchi, T,P M¢Creary, E Avetar, M Sheahan, R, Connolly, A, Santanen. E Ung~r, N, Pandian, Tufts- New England Medcal Center,

~ t o n , Mass, USA Background: Detection of intr~so~tar thrembu~ (IVT) is not always easy by COnventional ul~rase~nd in~tgmg, We explored the potential of a new contrast agent t~rgetedto throm~rs (MRX408) using a I@d synthesized with a fargetiog mo~etythat is an RG3 analog in the evaluation of in v~o Iv'r. Methods: We moated intravascu!ar thrombus (Iv'r) by inserting thrombin soaked cotton threads into the infenor vena cava (IVC) in 9 dogs, With a Commercially available 2-D ech¢cardiographic System, we recorded images of the IVC at baseline w~th no ¢t,ntrast agent, during COntinuous infusion of M R X l t 3 (a nontargetedcontrast agent as a Control) and intusmn o1 targeted agent, MRX408 Videointensity (VI, unitless) and the size of IVT (area) were analyzed blindly, Presence 0t IVT was venfied by autopsy. Results: In all instances of IVT, eff¢lent binding by the agent MRX408 and visually apparent increase in ultrasound contrast enhancement were noted. Vl o11VT was not different betwee't baseline and MRX113 (40.0 ± 14.6 and 73.9 ± 41.3, p = ns) but was hKjher dunng MRX408 infusion (105.7 ± 47.8, p < 0.05 vs. Baseline and vs MRX113). The maximum area of IVT was similar dunng baseline and MRX 113 (p = ns) but was found to be target dunng MRX408 thfusion by >41 ± 9%and >34 ± 14%, (P < 0.01 for each). Conclus~n: The tissue targeted contrast agent, MRX408 enhances the wsualtzation of IVC thrombus It has the potential to improve the diagnostic power for detecting and delineating intravascular thrombus, even when a conventional ultrasound imaging medaflty is employed.

Interventional Cardiology in Congenital Heart Disease M o n d a y . M a r c h 30. 1 9 9 8 . 1 0 : 3 0 a . m . - N o o n Georgia World Congress Center, Room 365W 10:30 ~

US/International M u i t i c e n t e r Trial of Atrial Septal

Catheter Closure Using the Amplatzer Septal Occluder: Initial R e s u l t s J. Masura, P E Lango, J.L Wilkinson, H H Kramer, M. Alwi. Y. Goussous. B. Thanopul0s, K.P. Walsh, Z.M HijaZL FOr the Aroplatzer Investigators,

The Children's University Hospital, Bratislava, Sfovek Republic and Tutts-New England Medical Center, Boston, MA, USA From 9/95-8/'97, 229 patients with secunduro atrial septal defect, 11 with patent foramen ovale and associated stroke and 3 with tenestrated Fortran undenNent transcatheter closure using the new self-centering, repositionable Amplatzer" Septal Occluder (ASO) at a median age of 6.6 yr (0.9-70 yr) and median weight of 22 kg (6.5-120 kg). The median size 0t the defect by 2D TEE was 12 rom (2-23 mm) and the median balloon stretched diameter was 15 mm (3-26 ram). The median size o1 the device (size of COnnecting waist beh,,,een the h'~odisks) used to close the detect was 15 mm (4-26 ram). In lew patients, both disks of the device were inadvertently opened either in the left or right atrium, because of the ability of repositioning the de~ce, eventually all patients had correct device deployment. The median fluoroscopy time was 16 min, (2.3-64 rain.) and median total procedure time was 90 rain, (27-139 rain.). Complications included were 2 device embolization to the RV with successful catheter retrieval and 1 endocarditis necessitating device removal and I with transient ischemic attack. At 24 hours by color Doppler, 74% of patients had complete (C) closure, 15% had trivial residual shunt (TS) and 6% had small residual shunt (SS). At one month follow-up by color Doppler, 91% of patients had C and 4.6% had TS and 2.8% had SS. No episodes of wire fracture or disruption. We conclude that the new ASO is safe and effective in completely closing most alrial communications.

T,M Zeltors, C,E, Mullins, M.R, Nthllt, RG, Gnfka, F,F Ing, gaYlOr College at

Medicine and Tex~s Chil~en~ Hospital, ~ n ,

T~, USA

Background: For patents with Postoperative pt.t!nlorlary artery =!lenoses, expandable intrevascu!ar slant placement is the treatment of choice. However, patients with postoperative t:dlatoml proximal pulm0nary artery ~efloses (PBPP$), with Closely related branch ost~, present a spec~l problem as proximal stent implantation rttRycompromise acces~ to the eontralateral ~dmona~ adery. We hypothesized that simullanoousty implanted cnsscmssing stents (SIXS) woutd be sate. wotdd improve bemodynamcca and allow future as;ass to both pulmonary arteries, MethO0~: Twenty patients (15 M; 69 ~ 6.9 yo; 5.6 ~ 4.2 y post.as) with PBPPS, with (n .. 9) and witho~ MPA stenosis, had SIXS between 1993 and 1997. The pnoclpal dmgnoses were dTGA (5), TOF (7), PA.VSD (41, Tmnctls (2) and AS/Ross procedure (1), We examined the change in RV:FA ratios, PA size and gradients, and branch sng!e wffh SIXS, RasfJffp: Hemodynamtca and vessel size improved significantly with SIXS (table), but branch angles were not stgniftcantly changed, Rali~ Grad,'ents(P~nHg) Vesselsize (ram] RVFA MPA-LPA MPA-RPA MPA LPA RPA Pre~tem 0 7 3 : 0 2 1 416~281 445":288 142±63 59-*20 67¢2.0 Post-slant 039¢0.12 94_.71 9 9 ¢ 8 1 19;2¢38 133~2S 131z24

Conclu~ons: SIXS provides excellem relief for pesloperatzve PBPPS white maintaining access tO both PAs and should be considered an excellent treatment choice for this problem. 11:00

~

Applicalion of Endovas©ular Stents o n t h e Management of Right Ventricular to Pulmonary Artery Conduit Stenosls

C OvaerL CA. Catdarone. B.W. McCnndte, D. Nykanen. R M Freedom. LN. Benson. The Hospital for Stck Children, Unwersdy of Toronto, Toronto,

Canada Background; Extracardiac conduits between the RV and pulmonary artenes commit patlents to multiple reoperations. Endovascular stenting of a stenot¢ conduit may delay reoporation. Methods; From 7/90 to 5/97. 42 patients underwent transcatheter stent insedion to relieve RV conduit stenosis Median age at procedure was 5.9 yrs (range, 6 me-17 yrs). with a median inten/al from conduit insertion of 24 ym (3 mo-13.9 yr'3). Clinical, echo, hemodynareic, ang~ographic and follow-up data were obtained. Results: RV systolic pressures decreased from 71 ± 18 mmHg to 48 ± 15 mmHg (p = 0.0001) after slant placement, with an increase in the minimal diameter of the COnduit of 51 ± 44% (p = 0,0001), No major complications occurred. Eleven pts had 1 and 2 pts had 2 additional tronscathetar interventions to fudhcr dilate the slant or add an additional slant, Surgcal conduit replacement was required in 17 pts at a mean of 20 • 16 me after the slant placement. Of those without surgery, 12 pts have been followed <1 y. the remainder UP to 5.4 yrs with 1 late death at 2.8 yrs after stent placement. Freedom from surgical intervention was 62% at I yr, 66% at 2 yr and 39% at 3 yr after stenting There was no effect on freedom from surgery of pt age or duration of conduit at stenting, but higher initial RV pressures predicted decreased palliation, with a trend towards improved eady results in the 2nd half of the study. Conclusions: Transcatheter placement of endovsscular stents tn stenotic RV conduits significantly delays conduit replacement. 11:15 [-804--0"4~-4 M a n a g e m e n t of Pulmonary A r t e r y Trauma due to L / B a l l o o n Dilation C.M. Baker, F.X. McGowan. J E Lock, J.F. Kea=o. The Children's Hospital.

Boston, Massachusetts, USA Background: Balloon dilation (BD) of the pulmonary artery (PA) is important m the management of peripheral pulmonary stenosis. Successful BD requires a controlled tear of the PA, however complications ranging from small pseudoaneurysrns to PA rupture can occur. We report our expenence managing BD associated PA rupture. Methods: All records (1983-1997) for patients undergoing cardiac catheterization during which BD of a PA was performed were re,.-ewed using a corn-